Posts Tagged ‘global warming’

Looking back over the last few decades, I have the impression that the sub-topic of climate and climate change (in particular, global warming) has gone from being a marginal issue to dominating the environmental debate, e.g. in that the damage done by a certain technology, behavior, whatnot is primarily measured in terms of effect on global warming, “green house” gases, and similar, while more direct environmental effects are given less and less weight. My recollections of the 1980s include extensive debate around forest death, thinning of egg shells due to DDT, acid rain, local city pollution, and similar. Today, it is quite often just global warming this and global warming that… For instance, reading up a little on means of transportation for an example in a text on shallow knowledge, I found comparisons that focused almost exclusively on C02 emissions and other ways* that the different means might affect global warming—but aspects like local pollution, use of heavy metals, and whatnot were not or only tangentially mentioned.

*E.g. whether it was better or worse to have emissions high in the air, specifically with an eye on global warming.

I find this highly unfortunate for at least two reasons:

Firstly, there are many valuable environmental-but-non-climate topics that are not given their due weight in terms of political debate, public awareness, and actual counter-measures.

Secondly, considerable doubts has to be raised as to whether global warming is that bad a thing. This even under the assumptions that it does exist and is man-made.*

*I believe both assumptions to be true, but I have not personally looked into the research sufficiently deeply to have a definite opinion—in part because I consider the question secondary for the very reasons discussed here. (As for “personally”: I have learned the hard way that what politicians, journalists, and the like claim is not always correct—and very, very often simplistic or exaggerated. Correspondingly, I postpone final judgment until I have “seen for myself”.)

Reading this second point, half the readers and almost all the environmentalist readers might not believe their eyes, but there are (again) at least two reasons for this statement:

Firstly, we are in an era of the Earth’s history which is quite cold. In fact, we are in (an inter-glacial* phase of) an ice age… Looking at most of the known record, it has been warmer or considerably warmer.** If the temperature rises further, we will only be leaving an atypical cold period—not entering an atypical warm period. (Unless the trends get entirely out of hand.) We might bring the Earth to a certain new temperature range earlier or faster*** than what the non-human processes would have managed, but it would have gotten there anyway, sooner or later.**** Moreover, it is conceivable that the global warming is counter-acting a further fall of temperature that might otherwise already have started (or, if not, would likely start within some thousands of years). Such a fall of temperature, leading into a glacial phase, would be as bad or worse as a rise for non-human species—and almost certainly much worse for us humans.

*Ice ages are divided into glacial and inter-glacial phases, depending on the spread of ice. Sloppy language often misuses “ice age” to refer specifically to a glacial phase.

**Cf. e.g. Wikipedia’s Timeline of glaciation article. Note that common journalist claims like “the hottest July of all times” are outrageously wrong, and might well contribute to the common misconceptions discussed below. In reality, it is merely the hottest July since the beginning of measurements—with measurements usually going back to some point in the 19th century. (The exact time depends on the country in question.)

***A faster change, obviously, increases the risk that some species will be unable to adapt in time. This aspect should not be neglected (but also see below).

****And continued to alternately grow warmer and colder again and again and again, long after humanity has become extinct.

Secondly, of the human made changes that occur, such a warming would be a comparatively small issue in a longer perspective. While even the sum of all human activities are dwarfed by various mass extinctions, specifically global warming is almost negligible in destructive* impact on a geological scale. (In contrast, a further-going destruction of the ozone layer could have had far worse consequences before sufficient adaptions occurred. Or consider the many extinctions that humanity has caused or could in the future cause through over-hunting/fishing, farming, introduction of foreign species, …—all on a time-scale that makes adaption hard.)

*This restriction is important, because it could lead to extensive changes that are not destructive, e.g. because they allow for various species to relocate or adapt.

The hitch is that too many fail to realize that the world we live in is ever-changing, was so before humans arose, and will continue to be so after we are gone. Temperatures change, coast-lines change, the positions of land-masses change, ocean streams change, … Even the position of the Earth’s magnetic poles change. If someone takes a human life-span, or even the life-span of some nations, as the scale of comparison, it might seem that higher temperatures, less ice, a higher sea-level, whatnot, are drastic changes. Using time-scales of a few thousand, often even few hundred, years, gives a very different perspective—and applying a time scale of millions of years makes it seem almost ridiculous. As a variation of the same theme, assume that most of New York were to be lost due to rising water—cataclysmic, disastrous, uprooting millions of people, causing billions upon billions of dollars of damage, … Or? Another perspective is that most of the current buildings and almost all of the population have been there for less than a hundred years. On a scale of two hundred years, the citizens of today and of yore would be hard-pressed to even recognize the respective other version of the city as New York—starting with the population of yore being a fraction of what it is today. A “New New York”, further inland, might exceed the old New York within decades, and certainly* within a hundred years. Moreover: if the change was slow enough, the negative effects might be largely counter-acted by minor changes to independent events, e.g. that people have a decreased tendency to move there and an increased tendency to move away, that newly founded companies are less likely to head-quarter there, and similar.

*Barring other developments and complications, many of which would have impacted New York too, and assuming that a corresponding re-founding took place (other choices are possible).

Realistically speaking, the destructive effects of climate changes (of the currently projected size) could hit current human society hard, but when we look at the long-term prospects of humanity, human society, or most non-human species, the effects will be smaller and/or transient. Of course, such threats to current human society are of great importance, but not for “environmental” reasons and it is dubious to frame the debate mainly as an environmental or a “save nature from humans” one.

Excursion on reasons for the shift in focus:
Apart from the use of inappropriate time scales, I suspect three factors behind the shift in focus: Firstly, many of the “old” threats have been averted, turned out to have been exaggerated (notably, forest death), or have lost their appeal to the masses (e.g. because a threat of extinction has been present for decades without the point of extinction actually being reached). This has lead both to these specific threats fading from the discussion and to similar other threats appearing less dire. Secondly, the scope of climate changes make them a very useful noble cause for politicians looking for voters, movements looking for followers, and similar. Thirdly, climate issues might well have been under-discussed at earlier times, because the awareness of their existence was not there. (More generally, the history of environmental protection contains a long series of discoveries that what-we-thought-was-harmless-might-actually-be-harmful, e.g. with CFCs and the ozone layer.)

Excursion on other damage vs. natural changes:
To some degree, other types of environmental damage, extinctions, whatnot, can be vulnerable to similar counter-arguments. For instance, sooner or later any given species will either go extinct or develop into another species—if humans do not exterminate the black rhino it will still go disappear at some later time, following the footsteps of e.g. the triceratops. I would, however, not use this type of reasoning to declare human-caused extinctions harmless: human intervention reduces species diversity, intra-species genetic diversity, and causes “unnatural selection”, all with a much deeper impact than global warming. If it had been “just” the black rhino, I might have let the argument hold—but the number of species concerned is much larger. Indeed, if we look at e.g. mammals in Europe, there are few, if any, species that have not been impacted by humans, be it through hunting of the species, hunting of the species’ predators or prey, shrinking biotopes, pollution, commensualism with humans, … True, if humans were to go extinct today, nature would ultimately bounce back; and true, the impact is still much smaller than that of the presumed dinosaur-killing asteroid. However, it is also much larger than impact from gradual global warming.